iMac Video Card Dead?

Taking a look at a friend's broke iMac - White 24" - can't place the model. EMC 2111 is the best I can pull off the case. Entering the serial at Apple just says 24" iMac, no year, nothing.

After tons of testing I've figured out the following...

1. Screen boots from grey, to apple logo with spinning loading circle, then to light blue. The cursor is stuck in the upper right hand corner. The screen stays blue. There's visual artifacts all over the screen - almost like stuck pixels.

2. Finally got the bright idea to plug in an external monitor. Once fully booted I see lit black screen with pixels artifacted, like they're stuck - not 1 or 20 or 50, like 100s, maybe 1,000. Now I can move the mouse cursor from screen to screen. The cursor that was previously stuck in the upper left hand corner of the iMac built in screen is still stuck there.

3. With the external monitor plugged in I can make OS X make error *dong* sounds. I'm assuming I'm booted into OS X and looking at the desktop but the video card is refusing the refresh/display any graphics.

Is the video card dead / dying? Any suggestions? I don't have any installation media to boot to and attempt a hardware test - typing from a refurb Lion that came with zero media. Attached photos: The blue monitor is the iMac, black = external.

The last time new White 24" iMacs were sold was mid 2007 (if I'm reading things correctly). Anyway, it's either a corrupted OS install or a video issue. You really need to find a bootable OS X DVD that will work on that system to find out. for sure.

Tapped the power button to put it to sleep. Got the pulsing glow sleep light on the front. Tapped the power button to bring it back - screen came on (black, but lit). Only the iMac, not the external. Then the backlight powered off. Hard shutdown (held power for 8s). Powered up. Video on both monitors! No Artifacts. Trying to get the damn password to update OS X, hopefully there's some damn video driver updates in there.

Taking a look at a friend's broke iMac - White 24" - can't place the model. EMC 2111 is the best I can pull off the case. Entering the serial at Apple just says 24" iMac, no year, nothing.

After tons of testing I've figured out the following...

1. Screen boots from grey, to apple logo with spinning loading circle, then to light blue. The cursor is stuck in the upper right hand corner. The screen stays blue. There's visual artifacts all over the screen - almost like stuck pixels.

2. Finally got the bright idea to plug in an external monitor. Once fully booted I see lit black screen with pixels artifacted, like they're stuck - not 1 or 20 or 50, like 100s, maybe 1,000. Now I can move the mouse cursor from screen to screen. The cursor that was previously stuck in the upper left hand corner of the iMac built in screen is still stuck there.

3. With the external monitor plugged in I can make OS X make error *dong* sounds. I'm assuming I'm booted into OS X and looking at the desktop but the video card is refusing the refresh/display any graphics.

Is the video card dead / dying? Any suggestions? I don't have any installation media to boot to and attempt a hardware test - typing from a refurb Lion that came with zero media. Attached photos: The blue monitor is the iMac, black = external.

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I had very similar problems to this on my first hackintosh. It was a driver conflict between my sound card and my video card. I'd make sure to up date ALL of your drivers to make sure something else isn't interfering. I don't know if it helps, but that's all I got.

Things are running a lot smoother this morning. After numerous reboots I'm booting just fine. Trying to get the damn thing updated. It only has 1GB of memory (stock) - trying to find some ram to bump it to the chipset max of 3GB (ugh - stupid intel chipset). I keep getting spinning beachballs when trying to do more than one thing. Guess I'm used to 8GB/Corei5.

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